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Latest Outlook
Outlook map for March 2023

March 2023 Hydrological Outlook

Period: From March 2023      Issued on 08.03.2023 using data to the end of February 2023

The Outlook for March and for March-April-May as a whole is for river flows and groundwater levels to be normal to below normal across the UK. Notably low river flows and groundwater levels may persist across large parts of central and southern England. Above normal groundwater levels are likely in some parts of the Chalk and Permo-Triassic sandstones.


Rainfall for February has been extremely low, with less than 30 percent of average seen across almost the entirety of central and southern England and Wales. Below average rainfall was also seen across the rest of the UK, with the exception of the northern Scottish highlands that saw average to slightly above average rainfall for February.

The forecast (issued by the Met Office on 27.02.2023) shows a higher than average likelihood (1.5 times the normal chance) that March, and March-April-May will be dry for the UK overall, with a decreased likelihood of a wet March and spring. Despite this UK-wide context, there is a greater chance of wetter spells of weather over southern parts of the UK in March, with north and north-eastern areas more likely to be drier than average.

River flows:

River flows in February closely followed the rainfall pattern received, with normal to exceptionally low flows across the UK, with the exception of parts of the Scottish highlands. Record breaking low flows were recorded in the Trent, Warleggan and Annacloy, with exceptionally low flows seen across large parts of central and south-western England.

River flows for March and March-April-May as a whole are likely to remain normal to below normal, with a high chance of exceptionally low flows in places. Flows in southern England and Wales may increase from their February levels in March due greater amounts of rainfall anticipated in these regions.


Groundwater levels in February were generally normal to below normal, with some above normal levels recorded in the south-eastern Chalk and sandstones of central England. Levels responded quickly to February’s low rainfall and started an early recession at several sites. Record breaking low levels were recorded in Greenfield Grange in south Wales.

Groundwater levels are likely to be normal to below normal across most of England and Wales for the next three months, and likely notably low in parts of the Chalk of southern England and the Jurassic limestones. Above normal levels are expected to continue in the eastern South Downs Chalk and northern Permo-Triassic sandstones.